Counterfeit products are becoming an ever greater problem with great economic implications, extending as far as danger to human health. In the case of counterfeited medicines there is even a danger to human life.
To counter counterfeit medicines and recognize counterfeit medicines in circulation, in addition to characteristics that are difficult to copy, such as watermarks, seals or special color markings for example, so-called auto ID (Identification) technologies such as barcodes or RFID (Radio Frequency Identification) systems are used. In such cases there are in particular two approaches that are followed to detect counterfeit medicines with certainty.
The first approach is based on a track-and-trace system in which the movements of a medicine are logged within the whole logistics chain. In such cases a globally unique serial number known as the Electronic Product Code (EPC) is read automatically by means of barcode or RFID and written into a central database when goods are dispatched and received. In order to now check whether an original medicine is involved, the data in the database is checked for consistency. If for example the same serial number occurs at two different locations at the same time, it is highly likely that the medicine has been counterfeited. However this approach has the problem of all participants in the delivery chain having to support this central database infrastructure.
The second approach is based on a cryptographic authentication of the RFID tags. Conventional RFID chips with a serial number can be cloned easily by personalizing other RFID chips with precisely this serial number. Ultimately it is impossible to distinguish any longer between the original and the cloned RFID chip. Cryptographic RFID chips on the other hand use a cryptographically-secured authentication and can thus securely prevent the cloning of authentication information. To this end the RFID chip is no longer a pure data memory but automatically executes cryptographic algorithms which require the knowledge of secret key information. A particular advantage of this process is the authentication by means of asymmetric cryptographic methods in which no secret information is necessary in the RFID reader itself in order to perform the check. The RFID reader merely needs the public signature key of the brand manufacturer to check any given RFID chip in order to thus be able to check the validity of the individual public key received from the RFID chip. In decentralized infrastructures in particular there is thus the option of verifying the authenticity of RFID chips and thus also of the product, without any complex central key management or an online transaction being necessary to do this.
However the disadvantage of this is that the RFID tags have to be deactivated after use. Otherwise the RFID tags from discarded blisters of an original medicine could be released and used again with a counterfeit medicine. A consequentially necessary deactivation by physical or protocol means, in addition to the technical outlay, always requires a deliberate action. Since the deactivation above all entails a benefit for the medicine manufacturer this merely entails extra expense for the user in the first instance.